1. Department of Mathematical Sciences; College of Science, United Arab Emirates University; Al-Ain 15551 UAE
2. Institute for Intelligent Systems Research and Innovation (IISRI), Geelong Waurn Ponds Campus, Deakin University; Australia
3. Department of Mathematics; Bharathiar University; Coimbatore Tamilnadu 641 046 India
4. Department of Mathematics; Gandhigram Rural Institute; Gandhigram Tamilnadu 624 302 India